Tokyo Metropolitan Police arrested Seiichi Tatai, 54, on suspicion of attempted coercion after he used a public payphone in Tokyo to call the Boat Race Marugame track in Marugame City at around 6 p.m. and threaten to spread sarin gas.

Tatai has admitted to the charges. He allegedly singled out a female racer and said: “I’ll spread sarin gas. You best tell management that she has to step down.”

Multiple suspicious phone calls were made to the boat race track from Wednesday to Thursday. Police were investigating outgoing call records when an investigator spotted Tatai using the payphone.

Police are investigating whether Tatai is tied to numerous other phone calls in which bomb threats were made to the same track in Marugame and another in Naruto City, Tokushima Prefecture last month.

Organizers of both tracks were forced to suspend races and evacuate visitors as well as staff.